1. Field of the Invention
The present invention relates to deflection gauges and more particularly pertains to a new deflection gauge dislodging system for performing deflection tests of pipes while permitting the deflection gauge to be readily dislodged from the interior of the pipe should it become stuck in the pipe.
2. Description of the Prior Art
The use of deflection gauges is known in the prior art for measuring the existence of any significant deflection of the perimeter wall of a pipe in a manner that may affect the roundness of the pipe and/or partially reduce the cross sectional opening area of the pipe after the pipe has been placed (such as in a buried condition underground). This deflection of the perimeter wall may occur due to, for example, improper backfilling of the trench in which the pipe is laid, or a deterioration of the perimeter wall of the pipe over a period of time.
One deflection gauge known in the art employs a pair of spaced end plates and a plurality of elongated skids that are mounted on and extend between the spaced plates. This type of deflection gauge is inserted into a pipe with the elongate skids oriented substantially parallel to the longitudinal axis of the pipe, and the end plates are oriented transverse to the longitudinal axis of the pipe. The elongate skids are circumferentially spaced about the substantially cylindrical outer periphery of the deflection gauge, and the outer surfaces of the elongate skids may be precisely calibrated to the desired inner diameter for the pipe to be tested. Eyes are rigidly and non-movably mounted on each of the end plates, and cords or ropes are generally attached to both eyes of the gauge for pulling the gauge through a length of the buried pipe (usually between separated access points in manholes). If the deflection gauge of the appropriate inner diameter size moves freely through the interior of the pipe, it is known that the portion of the pipe tested has an inner diameter that is at least as great as the calibrated diameter of the deflection gauge, and little if no deflection has occurred in the tested portion of the pipe.
However, in pipes in which the perimeter wall has been deflected and the inner diameter has been reduced, a deflection gauge calibrated to the appropriate inner diameter of the pipe will in most cases be prevented from moving through the interior of the pipe by the deflection of the wall. Thus, the deflection gauge cannot continue to be pulled through the pipe once it has encountered the deflected wall area, and its movement has to be reversed in the direction from which the gauge came. This is accomplished by pulling on the cord that was trailing the gauge as it moved forward through the pipe. In some cases, the movement of the gauge into the area of the pipe in which the perimeter wall has been deflected can cause the gauge to become lodged or stuck in the area of decreased diameter, especially since tension on the leading cord may not be released immediately when the pipe wall deflection stops the gauge from moving. Often an attempt is made to yank the trailing cord from a loose condition to a taut condition in an attempt to jar the gauge free from the perimeter wall, although this technique can be difficult to perform, especially when the pipe is underground and access is only gained through a manhole. Typically, the apparatus for pulling the cord is located outside of the manhole and above ground, which makes it even more difficult to achieve a sufficient jerk of the cord to dislodge the deflection cord. This technique has proved to be unsatisfactory in many instances for dislodging the gauge, and thus a better way of dislodging stuck deflection gauges has been desired in the art.
In view of the foregoing disadvantages inherent in the known types of deflection gauges and known techniques for dislodging the deflection gauges, the present invention provides a new deflection gauge dislodging system wherein the same can be utilized for performing deflection tests of pipes while permitting the deflection gauge to be readily dislodged from the interior of the pipe should it become stuck in the pipe.
To attain this, the present invention generally comprises an elongate deflection gauge for measuring a minimum diameter of a lumen of a pipe and dislodging means for dislodging the deflection gauge from a lodged condition in the lumen of a pipe. The dislodging means is adapted to impact against the deflection gauge while the deflection gauge is positioned in the lumen of the pipe.
In one embodiment of the invention, the dislodging means may be movably mounted on the deflection gauge, and the dislodging means may be movable with respect to the deflection gauge in a direction oriented substantially parallel to the longitudinal axis of the deflection gauge. The dislodging means may be adapted to impact the deflection gauge in a direction oriented substantially parallel to the longitudinal axis of the deflection gauge. The dislodging means may include a slide member slidably mounted on the deflection gauge, and at least one stop member mounted on the slide member for limiting sliding movement of the slide member with respect to the deflection gauge.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.